A related art window and door system will be described with reference to the accompanying drawings.
FIG. 1 is a front view showing a window and door to which a related art window and door system is applied. FIG. 2 is a sectional view taken along line A—A of FIG. 1.
The related art window and door system includes a window frame lower member 1 and window leaf lower members 2a and 2b. The window frame lower member 1 is provided with exposed rails 11. The window leaf lower members 2a and 2b are provided with rollers 21 mounted and arranged on the rails 11, and are guided by mohair members 22 and the rails 11 to open and close.
In the aforementioned related art window and door system, since the window leaf is opened and closed depending on the exposed rails, rainwater is drained out between the rails. For this reason, air tightness, water tightness, and thermal insulation cannot be improved. This could lead to low energy efficiency.
Furthermore, since the window leaf is inserted into the window frame, it is simple to assembly and disassembly the window leaf. However, it is likely that the window leaf is detached due to strong wind or manipulation. Accordingly, when the window leaf is used in a multistoried building, the window leaf is likely to be fallen down by being detached from the window frame. This causes dangerous situations.
Moreover, since stains of dust and rainwater piled between the rails are not easily removed, cleaning is difficult. If the piled dust is left uncleaned, the piled dust is raised when opening and closing the window leaf, thereby causing the air to be impure. It is therefore difficult to maintain a clean state. It a drainage outlet for rainwater between the rails is blocked by the dust and the like, or in case of a heavy rain accompanied by strong wind, damage may occur due to the rainwater. Also, an uneven lower structure has limitation in improving the appearance of the window and door system.